Ectoparasites can negatively affect their host with varying severity. The family Cimicidae, colloquially known as bed bugs, includes the obligate hematophagous Mexican chicken bug (Haematosiphon inodora). H. inodora populations have expanded north for 20 years and have been observed in Golden Eagle (Aquila chrysaetos) nests in Southern Idaho. Nestlings may be susceptible to effects of ectoparasites, like reduced body condition and mortality, because of their inability to evade the parasite. Exposure to H. inodora may elicit a stress response by the Hypothalamic–pituitary–adrenal (HPA) axis, increasing corticosterone (CORT) levels. We hypothesized that H. inodora in nests of Golden Eagles will reduce physiological condition and increase the HPA stress response of nestlings. We entered nests when nestlings were 4 and 7 weeks old, measured mass, collected blood, and noted the presence of ectoparasites. We evaluated physiological condition using hematocrit, body mass, and assayed plasma for CORT. Preliminary results suggest hematocrit and mass were significantly lower in nestlings with ectoparasites. This impaired physiological condition is likely to impact survival of Golden Eagles.